The concrete smeared crack model is used to simulate the plain concrete. The concrete-smeared crack model assumes that the monotonic load is applied to concrete under low confining pressure. The low confining pressure corresponds to the stress less than 1/5 to 1/4 of the maximum compressive strength of concrete. For reinforced concrete, the embedded elements are used. In this case, effects such as bond slip from the interface of concrete and steel are considered through tension stiffening.

The concrete smeared crack model simulates the compression part of concrete using a typical isotropic elasto-plastic model, and the tensile part of concrete is simulated using a smeared crack model. The smeared crack model is a method of simulating the crack by adjusting the stress and stiffness at the integration point, without reconfiguring the mesh. In the smeared crack model, the band-width obtained based on the size of the element is reflected in the crack behavior to avoid mesh dependencies (Bazant and Oh 1983). The square root of an area for a two-dimensional element and the cubic root of a volume for a three-dimensional element are the crack width of the element. For the higher order element, the half of the square root and the cubic root are the crack width. The tensile/compression uniaxial behavior of the concrete smeared crack model is shown in the figure below.